1. Field of the Invention
This invention relates to a substrate processing method and a substrate processing apparatus for processing using a processing liquid on a substrate to be processed. Examples of the substrate to be processed include a semiconductor wafer, a glass substrate for a liquid crystal display device, a substrate for a plasma display, a substrate for an FED (Field Emission Display), a substrate for a photomask, a substrate for an optical disc, a substrate for a magnetic disc, a substrate for a magnetic optical disc, a ceramic substrate and a substrate for a solar cell.
2. Description of Related Art
In the manufacturing process of a semiconductor device or a liquid crystal display device, on a substrate such as a semiconductor wafer or a liquid crystal display panel glass substrate, processing using a processing liquid such as a chemical liquid or a rinse liquid is performed. A substrate processing apparatus of a single substrate processing type adopted to perform processing a single substrate at a time with a processing liquid includes a spin chuck which holds the substrate substantially horizontally and rotates it and a processing liquid nozzle which supplies the processing liquid to the substrate held by the spin chuck. A processing liquid pipe is connected to the processing liquid nozzle.
Japanese Unexamined Patent Application Publication No. 2005-302746 discloses an arrangement in which in order to prevent a processing liquid from dripping from a processing liquid nozzle, nitrogen is introduced into a processing liquid pipe through a mixing valve. By the nitrogen introduced into the processing liquid pipe, the processing liquid present within the processing liquid nozzle and within the processing liquid pipe is extruded and is discharged from the processing liquid nozzle. The introduction of the nitrogen into the processing liquid pipe is continued until the processing liquid is completely discharged from the interior of the processing liquid nozzle and the interior of the processing liquid pipe.